[13] disable part files for object stores

[icewind1991]

Backport of #8715

[codecov]

Codecov Report

Merging #8725 into stable13 will decrease coverage by <.01%.
The diff coverage is 25%.

@@ Coverage Diff @@## stable13 #8725 +/- ##
==============================================
- Coverage 51.3% 51.29% -0.01% - Complexity 25017 25019 +2 
==============================================
Files 1609 1609 Lines 95285 95285 Branches 1376 1376 ==============================================
- Hits 48883 48881 -2 - Misses 46402 46404 +2

Impacted Files	Coverage Δ	Complexity Δ
...b/private/Files/ObjectStore/ObjectStoreStorage.php	66.39% <0%> (-0.56%)	75 <1> (+1)
apps/dav/lib/Connector/Sabre/File.php	74.04% <50%> (+0.18%)	102 <0> (+1)	⬆️
apps/files_trashbin/lib/Trashbin.php	72.28% <0%> (-0.25%)	136% <0%> (ø)